His statement contradicted the words of executive vice-chairman Ed Woodward 24 hours earlier, when he insisted the tour - which will see United travel almost 13,500 miles if they reach the final of the International Champions Cup - did not disrupt preparation.

Van Gaal, who met his players for the first time last week after leading the Netherlands to third place at the World Cup, said he was already making his presence felt at the club.

"The tour was already arranged so I have to adapt - and Manchester United shall do everything to adapt to my rules for good preparation," he said.

Wayne Rooney was picked out for praise during a training session ahead of the game against LA Galaxy

The 20-mile trip from the team hotel in Beverly Hills to Pasadena took in excess of an hour despite the assistance of a police escort, and Van Gaal apologised for his late arrival at a news conference to preview the encounter with LA Galaxy.

Asked if he would prefer a shorter tour next year he said: "Yeah, I hope that. And I am very confident that it shall be."

Tours have tended to become more long-haul as United's commercial operation has widened.

Not since 2002 have the club remained in Europe for an entire pre-season and last year they travelled in excess of 23,000 miles on a trip that included a week in Australia.

"The Premier League has been very clear in saying America is the number one developing market," said Woodward on Monday.

Former Manchester United and LA Galaxy midfielder David Beckham made the trip to see his old team

"This is a very good country from a potential sponsorship perspective."

After leading his team onto the pitch at Pasadena's Rose Bowl stadium in Tuesday's training session with a wave to the 2,500 spectators, Van Gaal then stood back and analysed as his coaches put the players through their paces.

Chris Smalling and Darren Fletcher were singled out when Van Gaal demanded to know why the pair had not looked at the ball during a shooting drill.

When Wayne Rooney completed the task to his new manager's satisfaction, Van Gaal made sure Smalling and Fletcher knew about it.

New signings Ander Herrera and Luke Shaw could make their debuts against La Galaxy in a game expected to attract a crowd in excess of 70,000.